BACKGROUND:Bone tissue loss caused by tumors and trauma can have an adverse effect on postoperative rehabilitation.Therefore,scaffold materials are usually implanted during treatment.However,the existing implant materials are relatively simple and lack antibacterial properties.Early implantation may lead to iatrogenic autoinfection and have an adverse effect on osteogenesis.OBJECTIVE:To construct a KR-12-a5 polypeptide-nanohydroxyapatite-small intestinal submucosa composite scaffold and evaluate its feasibility as a material for promoting bone defect repair.METHODS:The small intestinal submucosa scaffold and the small intestinal submucosa scaffold containing 25,50,and 100 mg/mL nanohydroxyapatite(referred to as nHA-SIS scaffold)were prepared by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride/N-hydroxysuccinimide cross-linking method.The appropriate scaffold was screened for subsequent experiments by mechanical property testing.The antibacterial properties of KR-12-a5 polypeptide solution against Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum were detected.The nHA-SIS scaffolds were immersed in 250,500,and 1 000 μg/mL KR-12-a5 peptide solutions for 24 hours,and then freeze-dried to obtain peptide-loaded nanohydroxyapatite-porcine small intestinal submucosa composite scaffolds(denoted as P-nHA-SIS scaffolds).The sustained-release properties of the three groups of scaffolds were characterized.The nHA-SIS scaffolds and the three groups of P-nHA-SIS scaffolds were co-cultured with Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum for 24 hours or 48 hours.The scaffolds with strong antibacterial ability were screened by live and dead bacteria staining and scanning electron microscopy for subsequent experiments.The degradation properties and water absorption rates of the uncross-linked small intestinal submucosa scaffolds,cross-linked small intestinal submucosa scaffolds,nHA-SIS scaffolds,and P-nHA-SIS scaffolds were characterized.The extracts of cross-linked small intestinal submucosal scaffolds,nHA-SIS scaffolds,and P-nHA-SIS scaffolds were co-cultured with MC3T3-E1 cells.CCK-8 assay and live-dead cell staining were performed.The effects of the extracts of the three scaffolds on the migration of MC3T3-E1 cells were detected by Transwell chamber assay.RESULTS AND CONCLUSION:(1)The elastic modulus and compressive strength of 25,50,and 100 mg/mL nHA-SIS scaffolds were higher than those of small intestinal submucosal scaffolds(P＜0.05),among which the elastic modulus and compressive strength of 25 mg/mL nHA-SIS scaffolds were the highest,and this group of scaffolds were selected for subsequent experiments to load peptides.(2)KR-12-a5 peptide had strong antibacterial activity against common bacteria in bone defects(Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum).The three groups of P-nHA-SIS scaffolds all had sustained release properties.With the increase of peptide mass concentration,the antibacterial property of P-nHA-SIS scaffold was enhanced.Among them,the P-nHA-SIS scaffold loaded with 500 μg/mL peptide had achieved a satisfactory antibacterial effect,and this group of scaffolds would be selected in the future.(3)The degradation rate of the three groups of cross-linked scaffolds was lower than that of the uncross-linked scaffolds,and the water absorption rate was greater than that of the uncross-linked scaffolds.P-nHA-SIS scaffolds could promote the proliferation and migration of MC3T3-E1 cells without affecting the activity of MC3T3-E1 cells.(4)The results show that P-nHA-SIS scaffolds have strong antibacterial properties and the ability to promote the proliferation and migration of MC3T3-E1 cells,and are expected to be used in bone defect repair.

BACKGROUND:Bone tissue loss caused by tumors and trauma can have an adverse effect on postoperative rehabilitation.Therefore,scaffold materials are usually implanted during treatment.However,the existing implant materials are relatively simple and lack antibacterial properties.Early implantation may lead to iatrogenic autoinfection and have an adverse effect on osteogenesis.OBJECTIVE:To construct a KR-12-a5 polypeptide-nanohydroxyapatite-small intestinal submucosa composite scaffold and evaluate its feasibility as a material for promoting bone defect repair.METHODS:The small intestinal submucosa scaffold and the small intestinal submucosa scaffold containing 25,50,and 100 mg/mL nanohydroxyapatite(referred to as nHA-SIS scaffold)were prepared by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride/N-hydroxysuccinimide cross-linking method.The appropriate scaffold was screened for subsequent experiments by mechanical property testing.The antibacterial properties of KR-12-a5 polypeptide solution against Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum were detected.The nHA-SIS scaffolds were immersed in 250,500,and 1 000 μg/mL KR-12-a5 peptide solutions for 24 hours,and then freeze-dried to obtain peptide-loaded nanohydroxyapatite-porcine small intestinal submucosa composite scaffolds(denoted as P-nHA-SIS scaffolds).The sustained-release properties of the three groups of scaffolds were characterized.The nHA-SIS scaffolds and the three groups of P-nHA-SIS scaffolds were co-cultured with Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum for 24 hours or 48 hours.The scaffolds with strong antibacterial ability were screened by live and dead bacteria staining and scanning electron microscopy for subsequent experiments.The degradation properties and water absorption rates of the uncross-linked small intestinal submucosa scaffolds,cross-linked small intestinal submucosa scaffolds,nHA-SIS scaffolds,and P-nHA-SIS scaffolds were characterized.The extracts of cross-linked small intestinal submucosal scaffolds,nHA-SIS scaffolds,and P-nHA-SIS scaffolds were co-cultured with MC3T3-E1 cells.CCK-8 assay and live-dead cell staining were performed.The effects of the extracts of the three scaffolds on the migration of MC3T3-E1 cells were detected by Transwell chamber assay.RESULTS AND CONCLUSION:(1)The elastic modulus and compressive strength of 25,50,and 100 mg/mL nHA-SIS scaffolds were higher than those of small intestinal submucosal scaffolds(P＜0.05),among which the elastic modulus and compressive strength of 25 mg/mL nHA-SIS scaffolds were the highest,and this group of scaffolds were selected for subsequent experiments to load peptides.(2)KR-12-a5 peptide had strong antibacterial activity against common bacteria in bone defects(Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum).The three groups of P-nHA-SIS scaffolds all had sustained release properties.With the increase of peptide mass concentration,the antibacterial property of P-nHA-SIS scaffold was enhanced.Among them,the P-nHA-SIS scaffold loaded with 500 μg/mL peptide had achieved a satisfactory antibacterial effect,and this group of scaffolds would be selected in the future.(3)The degradation rate of the three groups of cross-linked scaffolds was lower than that of the uncross-linked scaffolds,and the water absorption rate was greater than that of the uncross-linked scaffolds.P-nHA-SIS scaffolds could promote the proliferation and migration of MC3T3-E1 cells without affecting the activity of MC3T3-E1 cells.(4)The results show that P-nHA-SIS scaffolds have strong antibacterial properties and the ability to promote the proliferation and migration of MC3T3-E1 cells,and are expected to be used in bone defect repair.

OBJECTIVE: To identify prognostic genes associated with lysosome-dependent cell death (LDCD) in patients with gastric cancer (GC). METHODS: Differentially expressed genes (DEGs) were identified using The Cancer Genome Atlas - Stomach Adenocarcinoma. Weighted gene co-expression network analysis was performed to identify the key module genes associated with LDCD score. Candidate genes were identified by DEGs and key module genes. Univariate Cox regression analysis, and least absolute shrinkage and selection operator regression and multivariate Cox regression analyses were performed for the selection of prognostic genes, and risk module was established. Subsequently, key cells were identified in the single-cell dataset (GSE183904), and prognostic gene expression was analyzed. Cell proliferation and migration were assessed using the Cell Counting Kit-8 assay and the wound healing assay. RESULTS: A total of 4,465 DEGs, 95 candidate genes, and 4 prognostic genes, including C19orf59, BATF2, TNFAIP2, and TNFSF18, were identified in the analysis. Receiver operating characteristic curves indicated the excellent predictive power of the risk model. Three key cell types (B cells, chief cells, and endothelial/pericyte cells) were identified in the GSE183904 dataset. C19orf59 and TNFAIP2 exhibited predominant expression in macrophage species, whereas TNFAIP2 evolved over time in endothelial/pericyte cells and chief cells. Functional experiments confirmed that interfering with C19orf59 inhibited proliferation and migration in GC cells. CONCLUSION C19orf59, BATF2, TNFAIP2, and TNFSF18 are prognostic genes associated with LDCD in GC. Furthermore, the risk model established in this study showed robust predictive power.
Stomach Neoplasms/pathology* ; Humans ; Prognosis ; Lysosomes/physiology* ; RNA-Seq ; Cell Death ; Single-Cell Analysis ; Gene Expression Regulation, Neoplastic ; Cell Proliferation ; Single-Cell Gene Expression Analysis

OBJECTIVE: To explore the genetic basis for a woman with oocyte maturation disorder during assisted reproductive treatment (ART), and to verify the source of the variant and its impact on oocyte maturation through family verification. METHODS: A 35-year-old infertile woman presented at the Reproductive Medicine Center of Gansu Provincial Maternal and Child Health Care Hospital on 20 October 2023 for a 10-year history of infertility despite unprotected intercourse was selected as study subject. Peripheral venous blood sample was collected from the proband. Next-generation sequencing (NGS) was used to detect the potential variant. Candidate variants were validated within her family by Sanger sequencing, and their deleteriousness was assessed with comprehensive bioinformatic analyses to elucidate their origin and impact on oocyte maturation. According to the Standards and Guidelines for the Interpretation of Sequence Variants (hereinafter referred to as ACMG Guidelines) formulated by the American College of Medical Genetics and Genomics (ACMG), the pathogenicity of the candidate variant was rated. This study was approved by the Medical Ethics Committee of Gansu Provincial Maternal and Child Health Care Hospital (Ethics No.: 2023GSFYLS78). RESULTS: The proband underwent three controlled ovarian-stimulation cycles as part of assisted reproductive technology, yielding a total of 29 oocytes, among which only three were mature, whilst the remainders exhibited maturation arrest. Targeted sequencing of peripheral-blood DNA revealed a heterozygous c.728C>T (p.P243L) missense variant of the TUBB8 gene. While the same variant was detected in the proband's father. Based on the ACMG guidelines, the variant was classified to be likely pathogenic (PS4_Supporting+PM2_Supporting+PP2+PP3+PP4). CONCLUSION The heterozygous c.728C>T (p.P243L) missense variant of the TUBB8 gene probably underlay the oocyte maturation disorder in the proband, which may be either autosomal dominant or autosomal recessive. For probands with oocyte maturation disorders caused by the heterozygous c.728C>T variant of the TUBB8 gene, oocyte donation may be considered.
Humans ; Female ; Adult ; Mutation, Missense ; Oocytes/metabolism* ; Heterozygote ; Tubulin/genetics* ; Infertility, Female/genetics* ; High-Throughput Nucleotide Sequencing ; Pedigree

OBJECTIVE: To investigate the clinical phenotype and genetic etiology of a patient with primary infertility accompanied by Oocyte maturation defect (OOMD). METHODS: A 24-year-old female patient who visited the Reproductive Medicine Center of Gansu Provincial Maternity and Child Care Hospital in April 2024 was selected as the study subject. Whole-exome sequencing (WES) was performed on the proband and her husband. Candidate gene variants were validated in the family using Sanger sequencing, and compound heterozygous variants were confirmed through vector construction. Candidate variants were classified for pathogenicity according to the "Standards and Guidelines for the Interpretation of Sequence Variants" established by the American College of Medical Genetics and Genomics (ACMG). This study was approved by the Medical Ethics Committee of the Hospital [Ethics No.: (2023) GSFYLS(78)]. RESULTS: The proband, a 24-year-old female, had been unable to conceive for four years without contraception after marriage. She had undergone two ovarian stimulation cycles using the antagonist protocol and the PPOS protocol, respectively. A total of 74 oocytes were retrieved, with all showing OOMD and some oocytes exhibiting abnormal morphology and poor quality. WES results revealed two heterozygous missense variants in exons 14 and 16 of the PATL2 gene: c.1127G>A (p.R376Q) and c.1388C>G (p.A463G). Family validation results indicated that the missense variant in exon 14 was inherited from the proband's father, while the variant in exon 16 was de novo. CONCLUSION The compound heterozygous variants of the PATL2 gene probably underlay the OOMD and infertility in this proband. Further analysis based on the variant sites and protein structures is needed to determine whether PATL2 gene variants can fully affect oocyte development, thereby providing a personalized treatment plan for the proband.
Female ; Humans ; Young Adult ; Exome Sequencing ; Infertility, Female/genetics* ; Oocytes/metabolism* ; Pedigree ; Phenotype

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.

Objective To understand the changing composition and antibiotic resistance of bacterial species in the clinical isolates from outpatient and emergency department(hereinafter referred to as outpatients)and inpatient children over time in various hospitals,and to provide laboratory evidence for rational antibiotic use.Methods The data on clinically isolated pathogenic bacteria and antimicrobial susceptibility of isolates from outpatients and inpatient children in the CHINET program from 2015 to 2021 were collected and analyzed.Results A total of 278 471 isolates were isolated from pediatric patients in the CHINET program from 2015 to 2021.About 17.1％of the strains were isolated from outpatients,primarily group A β-hemolytic Streptococcus,Escherichia coli,and Staphylococcus aureus.Most of the strains(82.9％)were isolated from inpatients,mainly SS.aureus,E.coli,and H.influenzae.The prevalence of methicillin-resistant S.aureus(MRSA)in outpatients(24.5％)was lower than that in inpatient children(31.5％).The MRSA isolates from outpatients showed lower resistance rates to the antibiotics tested than the strains isolated from inpatient children.The prevalence of vancomycin-resistant Enterococcus faecalis or E.faecium and penicillin-resistant S.pneumoniae was low in either outpatients or inpatient children.S.pneumoniae,β-hemolytic Streptococcus and S.viridans showed high resistance rates to erythromycin.The prevalence of erythromycin-resistant group A β-hemolytic Streptococcus was higher in outpatients than that in inpatient children.The prevalence of β-lactamase-producing H.influenzae showed an overall upward trend in children,but lower in outpatients(45.1％)than in inpatient children(59.4％).The prevalence of carbapenem-resistant Klebsiella pneumoniae(CRKpn),carbapenem-resistant Pseudomonas aeruginosa(CRPae)and carbapenem-resistant Acinetobacter baumannii(CRAba)was 14％,11.7％,47.8％in outpatients,but 24.2％,20.6％,and 52.8％in inpatient children,respectively.The prevalence of multidrug-resistant E.coli,K.pneumoniae,Proteus mirabilis,P.aeruginosa and A.baumannii strains was lower in outpatients than in inpatient children.The prevalence of fluoroquinolone-resistant E.coli,ESBLs-producing K.pneumoniae,ESBLs-producing P.mirabilis,carbapenem-resistant E.coli(CREco),CRKpn,and CRPae was lower in children in outpatients than in inpatient children,but the prevalence of CRAba in 2021 was higher than in inpatient children.Conclusions The distribution of clinical isolates from children is different between outpatients and inpatients.The prevalence of MRSA,ESBL,and CRO was higher in inpatient children than in outpatients.Antibiotics should be used rationally in clinical practice based on etiological diagnosis and antimicrobial susceptibility test results.Ongoing antimicrobial resistance surveillance and prevention and control of hospital infections are crucial to curbing bacterial resistance.

Objective To investigate the changing antibiotic resistance profiles of E.coli isolated from patients in the 52 hospitals participating in the CHINET program from 2015 to 2021.Methods Antimicrobial susceptibility was tested for clinical isolates of E.coli according to the unified protocol of CHINET program.WHONET 5.6 and SPSS 20.0 software were used for data analysis.Results Atotal of 289 760 nonduplicate clinical strains ofE.coli were isolated from 2015 to 2021,mainly from urine samples(44.7±3.2)％.The proportion of E.coli strains isolated from urine samples was higher in females than in males(59.0％vs 29.5％).The proportion of E.coli strains isolated from respiratory tract and cerebrospinal fluid samples was significantly higher in children than in adults(16.7％vs 7.8％,0.8％vs 0.1％,both P＜0.05).The isolates from internal medicine department accounted for the largest proportion(28.9±2.8)％with an increasing trend over years.Overall,the prevalence of ESBLs-producing E.coli and carbapenem resistant E.coli(CREco)was 55.9％and 1.8％,respectively during the 7-year period.The prevalence of ESBLs-producing E.coli was the highest in tertiary hospitals each year from 2015 to 2021 compared to secondary hospitals.The prevalence of CREco was higher in children's hospitals compared to secondary and tertiary hospitals each year from 2015 to 2021.The prevalence of ESBLs-producing E.coli in tertiary hospitals and children's hospitals and the prevalence of CREco in children's hospitals showed a decreasing trend over the 7-year period.The prevalence of CREco in secondary and tertiary hospitals increased slowly.Antibiotic resistance rates changed slowly from 2015 to 2021.Carbapenem drugs(imipenem,meropenem)were the most active drugs amongβ-lactams against E.coli(resistance rate≤2.1％).The resistance rates of E.coli to β-lactam/β-lactam inhibitor combinations(piperacillin-tazobactam,cefoperazone-sulbactam),aminoglycosides(amikacin),nitrofurantoin and fosfomycin(for urinary isolates only)were all less than 10％.The resistance rate of E.coli strains to antibiotics varied with the level of hospitals and the departments where the strains were isolated,especially for cefazolin and ciprofloxacin,to which the resistance rate of E.coli strains from children in non-ICU departments was significantly lower than that of the strains isolated from other departments(P＜0.05).The E.coli isolates from ICU showed higher resistance rate to most antimicrobial agents tested(excluding tigecycline)than the strains isolated from other departments.The E.coli strains isolated from tertiary hospitals showed higher resistance rates to the antimicrobial agents tested(excluding tigecycline,polymyxin B,cefepime and carbapenems)than the strains from secondary hospitals and children's hospitals.Conclusions E.coli is an important pathogen causing clinical infection.More than half of the clinical isolates produced ESBL.The prevalence of CREco is increasing in secondary and tertiary hospitals over the 7-year period even though the overall prevalence is still low.This is an issue of concern.

Objective:To explore the genetic basis for a woman with oocyte maturation disorder during assisted reproductive treatment (ART), and to verify the source of the variant and its impact on oocyte maturation through family verification.Methods:A 35-year-old infertile woman presented at the Reproductive Medicine Center of Gansu Provincial Maternal and Child Health Care Hospital on 20 October 2023 for a 10-year history of infertility despite unprotected intercourse was selected as study subject. Peripheral venous blood sample was collected from the proband. Next-generation sequencing (NGS) was used to detect the potential variant. Candidate variants were validated within her family by Sanger sequencing, and their deleteriousness was assessed with comprehensive bioinformatic analyses to elucidate their origin and impact on oocyte maturation. According to the Standards and Guidelines for the Interpretation of Sequence Variants (hereinafter referred to as ACMG Guidelines) formulated by the American College of Medical Genetics and Genomics (ACMG), the pathogenicity of the candidate variant was rated. This study was approved by the Medical Ethics Committee of Gansu Provincial Maternal and Child Health Care Hospital (Ethics No.: 2023GSFYLS78).Results:The proband underwent three controlled ovarian-stimulation cycles as part of assisted reproductive technology, yielding a total of 29 oocytes, among which only three were mature, whilst the remainders exhibited maturation arrest. Targeted sequencing of peripheral-blood DNA revealed a heterozygous c. 728C>T (p.P243L) missense variant of the TUBB8 gene. While the same variant was detected in the proband′s father. Based on the ACMG guidelines, the variant was classified to be likely pathogenic (PS4_Supporting+ PM2_Supporting+ PP2+ PP3+ PP4). Conclusion:The heterozygous c. 728C>T (p.P243L) missense variant of the TUBB8 gene probably underlay the oocyte maturation disorder in the proband, which may be either autosomal dominant or autosomal recessive. For probands with oocyte maturation disorders caused by the heterozygous c. 728C>T variant of the TUBB8 gene, oocyte donation may be considered.

The scientific research and innovation capabilities of medical students are intrinsically linked to the sustained and high-quality development of national healthcare initiatives.Cultivating outstanding medi-cal students with independent scientific capabilities and innovative consciousness is a critical component in the education and training of high-level medical professionals.Our investigation revealed that within the imperfections of the cultivating model,some faculty and students at medical schools have an insufficient understanding of scientific research and innovation and lack motivation for engaging in such activities,which hinder the progression of scientific research activities.Consequently,we initiated a teaching practice and exploratory study on the"tutorial system"aimed at fostering medical students'scientific research and innovation abilities.Based on the principle of"research informing teaching,teaching and research advan-cing together,"this study implements a"tutorial system"coordinated by tutors,supplemented by graduate and undergraduate student mentors,to cultivate innovative thinking,stimulate interest in scientific re-search,and enhance practical and research skills among medical students.Through collaborative efforts within"scientific research innovation teams,"various educational methods—including preliminary re-search,in-class and extracurricular activities,intra-group and inter-group interactions,and theoretical and practical applications—are employed to improve and strengthen the cultivation of medical students'scientif-ic research and innovation abilities.This study aims to provide valuable references for optimizing medical education management systems and enhancing the quality of medical student training.